When driving I've noticed that my NAV display will sporadically display no antenna. I'll continue to hear the radio but I can't change the stations. A few minutes later it will come back on and be fine.

I may be crazy but this seems to happen while driving on the highway yet when travelling on tree covered roads it doesn't happen as much. Maybe this is just a coincidence????

Anyone experience anything like this?

I'm driving a 06 4.8is. Dealer installed the sirius.

Thanks